Diseases associated with thyroid autoimmunity: explanations for the expanding spectrum

Anyone who has been in an endocrine clinic will appreciate that associations exist between autoimmune thyroid disease (AITD) and other autoimmune disorders. However, the full extent of these associations is still not fully appreciated, and new associations are being uncovered which may shed new light on the pathogenic basis for these connections, and the underlying reasons for them are only now becoming understood. This review is based on the British Thyroid Association Pitt-Rivers Lecture 2010. The first section provides an update on studies which have detailed the strength of various autoimmune disease associations, the second section discusses the environmental and genetic factors which underlie these associations and the final section describes some recently identified, unexpected AITD associations. Unravelling these associations further will illuminate the pathogenesis of autoimmune diseases and offers the prospect of new therapeutic approaches.